1. Field of the Invention
This invention is related to interlacing jets and jet nozzles that are used with multifilament textile yarns. More particularly this invention is related to the use of tandem jet nozzles to improve the quality of the interlaced textile yarn.
2. Description of the Prior Art
Multifilament textile yarn can be interlaced or entangled using interlacing jets in which a relatively high velocity airstream is injected transversely of a yarn channel in the jet nozzle. U.S. Pat. No. 5,010,631 and U.S. Pat. No. 5,146,660 disclose two interlacing jet nozzles. The turbulent flow created by injecting a relatively high velocity jet of air into a transverse yarn channel serves to interlace or entangle portions of a multifilament yarn.
In some applications only a single jet nozzle is used to interlace the multifilament yarn, but it has been found that two jet nozzles of this basic type can be placed in tandem so that the multifilament yarn transits one jet before entering the second coaxial jet. In these tandem applications, guides are placed in front of the upstream jet nozzle and after the downstream jet nozzle. It has been found that this tandem jet arrangement will result in greater yarn uniformity at higher speeds on the order of 5000 to 6000 meters per minute.